Russian Losses in the Soviet Invasion of Poland

When Poland was invaded in September 1939 most focus on just the German invasion. However on the 17th of September the Soviet Red Army began invading as well. Many think the Russians just brushed aside any resistance here's what their invasion cost them.

Keep in mind these are Polish estimates as Russian estimates are always fewer then in reality. Also remember that Poland's best were busy fighting the Germans and in the East soldiers were going through speedy training.